Wireless communication is now becoming widespread in a variety of applications from cellular telephones to wireless networking. Wireless communication is also used in such devices as pacemakers, which may need to communicate to an external device carried outside the body. As people travel more, they have a need to take their wireless devices with them. The problem is that different parts of the globe have different regulations covering the use of radio frequencies. For example, in many frequency ranges no single frequency band can be used worldwide.
Where the communications device is static this is not a problem because the appropriate characteristics can be chosen at the time of installation. However, it does present a problem for body-worn, hand-held and portable systems, where the device must be used in several different places and where the device must communicate with a partner device, such as a controller. Currently, there is no way to design a device that can be legally used everywhere. For example, a pacemaker communicating with a control unit may be legal in the United States but illegal in Europe.
It is known, for example, from GB patent no. 2,371,713 to determine the position of a mobile device and reconfigure it automatically as it moves to a remote location. The prior art does not address the case of a pair of communicating devices, such as a pacemaker and controller, that may move location but that do not communicate with a base station and where there is no technical need to change the wireless characteristics of the communicating devices.